Thermal flow assembly including integrated fan

ABSTRACT

An electronic device includes an outer housing having an upper enclosure and a foot coupled thereto, a heat generating component, and a fan assembly integrated into the foot and situated proximate a bottom surface of the heat generating component. The foot can include inlet and outlet vents. The fan assembly can include an inlet, outlet, impeller with blades, shroud and fin stack. The electronic device can also include a heat pipe, a heat transfer stage, a PCB, and a bottom shield. Airflow through the electronic device can be directed across the fin stack, heat pipe, heat transfer stage, and bottom shield. Airflow can occur over a substantially level path through the electronic device from the inlet to outlet vents.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. Nonprovisional patentapplication Ser. No. 16/040,083, filed on Jul. 19, 2018 entitled,“THERMAL FLOW ASSEMBLY INCLUDING INTEGRATED FAN,” which is acontinuation of U.S. Nonprovisional patent application Ser. No.15/199,460, filed on Jun. 30, 2016 (now U.S. Pat. No. 10,034,411 issuedJul. 24, 2018) ‘THERMAL FLOW ASSEMBLY INCLUDING INTEGRATED FAN,” whichclaims the benefit of U.S. Provisional Patent Application No.62/233,261, filed on Sep. 25, 2015 entitled, ‘THERMAL FLOW ASSEMBLYINCLUDING INTEGRATED FAN,” which are incorporated by reference herein intheir entireties for all purposes.

FIELD

The described embodiments relate generally to electronic devices, andmore particularly to thermal management features for electronic devices.

BACKGROUND

Electronic devices contain components that produce heat during normaloperation. Fans, heat sinks, and other heat diversion components arethus well-known and common features in many electronic devices. As mightbe expected though, increasingly faster and more powerful chips andintegrated circuitry can generate more heat than previous generations ofdevices. Coupled with the desire to put these components into smalleroverall volumes, this can create new challenges. Existing thermalmanagement features and techniques can sometimes fall behind in the faceof increasing demands to account for more heat using less volume thanbefore. Even where minimal thermal requirements are met for a givenelectronic device, the overall performance of the device can be enhancedwhere its generated heat is well dispersed beyond the minimums that arerequired.

While current thermal management features and techniques for electronicdevices have worked well in the past, there is often room forimprovement. Accordingly, there is a need for improved heat dissipationfeatures and techniques in electronic devices.

SUMMARY

Representative embodiments set forth herein disclose various featuresand techniques for managing heat dissipation in an electronic device. Inparticular, the disclosed embodiments set forth electronic deviceshaving low profile thermal flow assemblies including integrated fans, aswell as the thermal flow assemblies, and also methods for cooling anelectronic device.

According to various embodiments, an electronic device includes an outerhousing having an upper enclosure and a foot coupled thereto, a heatgenerating component, and a fan assembly integrated into the foot. Thefan can be situated proximate a bottom surface of the heat generatingcomponent. The foot can include inlet and outlet vents. The fan assemblycan include an inlet, outlet, impeller with blades, shroud and finstack. The electronic device can also include a heat pipe, a heattransfer stage, a PCB, and a bottom shield. Airflow through theelectronic device can be directed across the fin stack, heat pipe, heattransfer stage, and bottom shield, and the airflow can occur over asubstantially level path from the inlet to outlet vents.

This Summary is provided merely for purposes of summarizing some exampleembodiments so as to provide a basic understanding of some aspects ofthe subject matter described herein. Accordingly, it will be appreciatedthat the above-described features are merely examples and should not beconstrued to narrow the scope or spirit of the subject matter describedherein in any way. Other features, aspects, and advantages of thesubject matter described will become apparent from the followingDetailed Description, Figures, and Claims.

Other aspects and advantages of the embodiments described herein willbecome apparent from the following detailed description taken inconjunction with the accompanying drawings which illustrate, by way ofexample, the principles of the described embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The included drawings are for illustrative purposes and serve only toprovide examples of possible structures and arrangements for thedisclosed features and techniques for managing heat dissipation in anelectronic device. These drawings in no way limit any changes in formand detail that may be made to the embodiments by one skilled in the artwithout departing from the spirit and scope of the embodiments. Theembodiments will be readily understood by the following detaileddescription in conjunction with the accompanying drawings, wherein likereference numerals designate like structural elements.

FIG. 1 illustrates in top perspective view an exemplary electronicdevice according to various embodiments of the present disclosure.

FIG. 2 illustrates in exploded perspective view an exemplary electronicdevice having a low profile thermal flow assembly according to variousembodiments of the present disclosure.

FIG. 3A illustrates in top perspective view an exemplary low profilethermal flow assembly for the electronic device of FIG. 2 according tovarious embodiments of the present disclosure.

FIG. 3B illustrates in partially exploded top perspective view the lowprofile thermal flow assembly of FIG. 2 having an outer housing footwith integrated fan assembly according to various embodiments of thepresent disclosure.

FIG. 4 illustrates in side elevation view the exemplary low profilethermal flow assembly of FIG. 3A according to various embodiments of thepresent disclosure.

FIGS. 5A-5C illustrate in top plan views various stages of a partiallyassembled exemplary outer housing foot with integrated fan assemblyaccording to various embodiments of the present disclosure.

FIG. 6 illustrates in side cross-sectional view an exemplary electronicdevice having a low profile thermal flow assembly according to variousembodiments of the present disclosure.

FIG. 7 illustrates in top perspective view an exemplary impeller and finstack arrangement for an integrated fan assembly according to variousembodiments of the present disclosure.

FIGS. 8A and 8B illustrate in bottom plan views exemplary foot andscroll geometries for an integrated fan assembly according to variousembodiments of the present disclosure.

FIG. 9 illustrates a flowchart of an exemplary method of cooling anelectronic device according to various embodiments of the presentdisclosure.

FIG. 10 illustrates in block diagram format an exemplary computingdevice that can be used to implement the various components andtechniques described herein according to various embodiments of thepresent disclosure.

DETAILED DESCRIPTION

Representative applications of apparatuses and methods according to thepresently described embodiments are provided in this section. Theseexamples are being provided solely to add context and aid in theunderstanding of the described embodiments. It will thus be apparent toone skilled in the art that the presently described embodiments can bepracticed without some or all of these specific details. In otherinstances, well known process steps have not been described in detail inorder to avoid unnecessarily obscuring the presently describedembodiments. Other applications are possible, such that the followingexamples should not be taken as limiting.

Electronic devices contain components that produce heat during normaloperation. As such, fans, heat sinks, and other heat diversioncomponents are a well-known and common part of the electronicslandscape. Increasingly faster and more powerful circuitry can generateincreased levels of heat, while space constraints are often shrinking,both of which can create new challenges. Accordingly, there is a needfor improved heat dissipation features and techniques in electronicdevices.

According to various embodiments, an electronic device includes an outerhousing having an upper enclosure and a foot, a heat generatingcomponent, and a fan assembly integrated into the foot and situatedproximate the heat generating component bottom surface. The foot caninclude inlet and outlet vents, while the fan assembly can include aninlet, outlet, impeller with blades, shroud and fin stack. Theelectronic device can also include a heat pipe, a heat transfer stage, aPCB, and a bottom shield. Airflow through the electronic device can bedirected across the fin stack, heat pipe, heat transfer stage, andbottom shield, and the airflow can occur over a substantially level pathfrom the inlet to outlet vents.

The foregoing approaches provide features and techniques for managingheat dissipation in an electronic device, such as by using a low profilethermal flow assembly. A more detailed discussion of these features andtechniques is set forth below and described in conjunction with FIGS.1-10, which illustrate detailed diagrams of devices and components thatcan be used to implement these features and techniques.

Turning first to FIG. 1, an exemplary electronic device according tovarious embodiments of the present disclosure is illustrated in topperspective view. Electronic device 100 of FIG. 1 may be a computer, aset-top box, a wireless access point, a portable electronic device, orany other suitable electronic device or piece of equipment. In variousembodiments, electronic device can be a digital media extender (e.g., anApple TV®), for example. Electronic device 100 may have an outer housing102, which may be formed from materials such as plastic, glass, ceramic,metal, carbon fiber, fiberglass, and other fiber composites, othermaterials, or combinations of these materials, for example. Housing 102may have one or more parts, such as, for example, mating upper and lowerparts formed from plastic or other housing materials. If desired,housing 102 may have more than two parts.

In the configuration shown in FIG. 1, housing 102 of electronic device100 has a rectangular box shape with planar upper and lower surfaces andfour perpendicular (vertical) planar sidewalls, and the corners ofhousing 102 may be rounded. It will be readily appreciated that theexample of FIG. 1 is merely illustrative, such that other shapes may beused for housing 102 if desired (e.g., shapes with curved sides, shapeswith circular footprints, shapes with combinations of curved andstraight edges and surfaces, etc.). To accommodate connectors fordisplays, device peripherals, power cables, and other accessories,housing 102 may have openings (e.g., port openings) such as openings104. Electronic device 100 may also contain internal electroniccomponents, such as integrated circuits and other components that maygenerate heat. Thermal management features may thus be incorporated intothe internal structures of electronic device 100, and even withinvarious components of housing 102, such as set forth in greater detailbelow.

In FIG. 2, an exemplary electronic device having a low profile thermalflow assembly is illustrated in exploded perspective view. Electronicdevice 200 can include an upper enclosure 210 and a foot 220 coupledthereto to form an overall outer housing. A power supply unit 212 and aninternal antenna 214 can reside within an upper region of the overallouter housing, while a multi-level board 230 can reside in the overallouter housing beneath the power supply unit 212. Multi-level board 230can include one or more heat generating components (not shown), such asa CPU and various other processing components and circuitry, as well astop and bottom shields or heat spreaders coupled thereto, among otherpossible items. A heat transfer stage 240 can be disposed beneath themulti-level board 230, such as directly beneath the CPU or othersignificant heat generating component on multi-level board 230. This canresult in heat transfer stage 240 being in thermal contact with the CPUand/or other heat generating component(s), as will be readilyappreciated.

An air cylinder 250 can be disposed beneath heat transfer stage 240, andcan serve to limit or direct airflow within electronic device 200. Invarious embodiments, air cylinder 250 can form a shell or enclosure thateffectively isolates or at least separates various portions of anoverall low profile thermal flow assembly from other components withinthe overall electronic device 200. For example, a heat pipe 260 and finstack 270 can be disposed within a volume defined by air cylinder 250,while a fan assembly 280 can be disposed beneath these components andintegrated within the foot 220. In various embodiments, the heattransfer stage 240 might be considered part of an overall low profilethermal flow assembly, and the heat pipe 260 and/or fin stack 270 mightbe considered part of an overall fan assembly.

Moving next to FIG. 3A, an exemplary low profile thermal flow assemblyfor the electronic device of FIG. 2 is shown in top perspective view.Again, a low profile thermal flow assembly 300 can include a heattransfer stage 240 disposed outside of an air cylinder 250 that containsvarious other assembly components disposed therein. In alternativeembodiments, heat transfer stage 240 might be disposed within aircylinder 250 or another similar airflow restricting device. In eitherarrangement, heat transfer stage 240 can be in thermal contact with oneor more components inside of the enclosure formed by air cylinder 250.These items can all be integrated with or otherwise contained within afoot 220, which again can form a part of an overall external housing forthe electronic device 200.

FIG. 3B illustrates in partially exploded top perspective view the lowprofile thermal flow assembly of FIG. 2 according to various embodimentsof the present disclosure. As shown in partially exploded view 390, heatpipe 260 can be disposed directly beneath and in thermal contact withheat transfer stage 240 (with air cylinder 250 potentiallytherebetween), such that heat pipe 260 is configured to direct heat awayfrom a CPU or other heat generating component(s) within the multi-levelboard 230 disposed thereabove. Heat pipe 260 can extend from beneathheat transfer stage 240 into fin stack 270, where heat can then beexchanged with cooling air forced therethrough by an impeller 281disposed within a fan assembly 280.

Impeller 281 can have a hub 282 and blades 283, and can rotate such thatincoming cool air is pulled into and forced out of the impeller 281. Ashroud 284 can force or direct airflow from one or more fan assemblyinlets 285 over the top of impeller 281 and toward a central regionthereof where hub 282 is located. Shroud 284 then ends as shown, suchthat incoming cool air is pulled into the central region of impeller281, where rotation of blades 283 forces the air outward and into finstack 270. Air is then heated as it is forced or directed through finstack 270, after which the heated air is exhausted through one or morefan assembly outlets 286. One or more seals 287 can compress during theinstallation of fin stack 270 to fan assembly 280, and such seals 287can limit or further direct airflow in a desirable manner.

FIG. 4 illustrates in side elevation view the exemplary low profilethermal flow assembly of FIG. 3A according to various embodiments of thepresent disclosure. Low profile thermal flow assembly 400 can beidentical or similar to assembly 300 above, and thus can include a heattransfer stage 240 disposed outside of an air cylinder 250 that containsvarious other assembly components disposed therein. Foot 220 can be partof an overall outer housing for electronic device 200, and can includevarious thermal flow assembly items or features integrated therein. Forexample, one or more inlet vents 222 formed within foot 220 can allowambient air outside of electronic device 200 to enter the device forcooling airflow purposes. Similarly, one or more outlet vents 224 formedwithin foot 220 can allow heated air to be exhausted from the electronicdevice 200.

Air coming into, through, and out of low profile thermal flow assembly400 is generally designated as airflow 405. Air entering the devicethrough inlet vent(s) 222 can all or mostly be directed to fan assemblyinlet(s) 285, after which the air flows through the fan assembly asnoted above and reaches the fan assembly outlet(s) 286. Air reaching thefan assembly outlet(s) 286 has typically been heated by this point,whereby the heated air is then generally directed toward outlet vents224 where it is exhausted from electronic device 200. Airflow 405through low profile thermal flow assembly 400 can exchange heat withvarious device components, such that the air is heated and the variousdevice components are cooled, as will be readily appreciated. Airflow405 can thus serve to cool, for example, a bottom shield 231 ofmulti-level board 230, a heat transfer stage 240, a heat pipe 260, and afin stack 270, among other device components. Such cooling or heatexchanges can take place by way of direct or indirect contact withairflow 405.

FIGS. 5A-5C illustrate in top plan views various stages of a partiallyassembled exemplary outer housing foot with integrated fan assemblyaccording to various embodiments of the present disclosure. Arrangement500 in FIG. 5A depicts an outer housing foot 220 having a fan scrollgeometry integrated therein. Such fan scroll geometry items can includeone or more fan assembly inlets 285, one or more fan assembly outlets286, and an internal cavity shaped to house and facilitate thefunctionality of various other fan assembly items. Such other fanassembly items can include, for example, a rotatable impeller 281 havinga hub 282 and blades 283 that can rotate in fan direction 288.

Arrangement 501 in FIG. 5B depicts a shroud 284 installed on top of thearrangement 500 of FIG. 5A. As shown, shroud 284 can serve to restrictairflow, effectively turning various vents and openings into inlets andoutlets. Shroud 284 covers part of the top of impeller 281, such thatair is forced over the top of the impeller in some locations but notothers. This results in various openings within the assembly becomingfan assembly inlets 285 and other openings becoming fan assembly outlets286. Incoming or inlet airflow(s) 506 then enter the assembly throughone or more fan assembly inlets 285, and flows over the top of shroud284 before entering the impeller near its center or hub 282. The air isthen forced out of the impeller during rotation, as shown by outgoing orexhaust airflow(s) 507 exiting the side of the impeller and proceedingthrough one or more fan assembly outlets 286.

Arrangement 502 in FIG. 5C depicts a heat pipe 260 and a fin stack 270installed onto the arrangement 502 of FIG. 5B. As shown, heat pipe 260can extend from above hub 282 down into the fin stack 270, such thatheat is transferred from above the hub 282 (e.g., from heat transferstage 240) down into the fin stack 270. Outgoing or exhaust airflow canthen be forced through the fin stack 270 before it is exhausted from thefan assembly and device entirely, with such an interaction between theoutgoing airflow and the fin stack 270 resulting in a significantexchange of heat that heats the air before it is exhausted.

FIG. 6 illustrates in side cross-sectional view an exemplary electronicdevice having a low profile thermal flow assembly according to variousembodiments of the present disclosure. Electronic device 600 can beidentical or substantially similar to electronic device 200 above, onlyin fully assembled form. Electronic device 600 can thus have many or allof the same components of electronic device 200, such as, for example,upper enclosure 210, foot 220, power supply unit 212, multi-level board230, heat transfer stage 240, fin stack 270, and impeller 281, amongother items. Airflow 605 through the electronic device 600 can begin atinlet vent(s) 222 at an outer surface of foot 220, where it can proceedto fan assembly inlet(s) 285. In various embodiments, fan assemblyinlet(s) 285 can be formed at interior surface(s) of foot 220. As notedabove, airflow 605 can then proceed through the fan assembly, includingimpeller 281, and into fin stack 270, where the airflow 605 is heatedthrough contact with heated fins. The airflow 605 can then exit the fanassembly at fan assembly outlet(s) 286, after which it can exit theentire electronic device at outlet vent(s) 224. Again, fan assemblyoutlet(s) can be formed at an interior surface of foot 220, while outletvent(s) 224 can be formed at an outer surface of foot 220.

In general, much or all of airflow 605 is caused due to rotation of thefan, such as at impeller 281. This rotational fan operation pulls airinto the top of the fan, pushes air out of the other side of the fan,and creates the rest of airflow 605 by extension, due to operation ofthe fan assembly. When considered with respect to the height and size ofoverall electronic device 600, the full path for airflow 605 through theelectronic device occurs over a substantially level path from the inletvents 222 to the outlet vents 224. That is to say, the airflow 605 onlyvaries slightly up or down in a vertical or “z” direction during itsentire passage through the electronic device 600. More particularly,airflow 605 is mostly or completely limited to the volume created forfan assembly 280. Accordingly, little to no airflow passes through theupper regions of electronic device 600, such as at multi-level board 230or above. In some embodiments, designs can be implemented to allow for asmall amount of air to leak into and traverse through these upperregions, whereby the small amount of air can then also be exhausted atoutlet vents 224.

FIG. 7 illustrates in top perspective view an exemplary impeller and finstack arrangement for an integrated fan assembly according to variousembodiments of the present disclosure. Impeller and fin stackarrangement 700 can be set within a foot 220 of an outer device housing,which can include fan assembly inlets 285 and fan assembly outlets 286,as well as an impeller hub 282 and blades 283, which can define aspecific blade circumference or diameter 289. A scroll profile 226 canbe a contour that is integrally formed with or situated proximate to aninternal portion of foot 220. This scroll profile 226 can define how airwill flow and be controlled as it enters and proceeds through theimpeller 281.

Airflow 705 proceeding through the impeller is then forced out of theimpeller at the other side, where it passes between fins 272 of the finstack 270. Distance 274 between the outer edge of impeller 281 and thefin stack 270 can determine various airflow properties, such as speed,direction and acoustic effects. In various embodiments, distance 274 canbe adjusted or tuned so as to minimize acoustic effects of airflow 705passing through the fan assembly. This can be done, for example, byincreasing or decreasing the lengths of individual fins 272. Other itemsthat can be adjusted to minimize or eliminate acoustic effects caninclude the impeller diameter 289, as well as the count and angles ofimpeller blades 283, and also the dimensions of scroll profile 226,among other items and features. In various embodiments, airflow 705 canexit impeller blades 283 tangentially, with the arrangement and anglesof fins 272 set to account for such flow directions. Appropriate designof the arrangement and angles of fins 272 can then result in minimalchanges in directional changes and turbulence as airflow 705 moves fromimpeller 281 to fin stack 270. This can also result in minimizedacoustic effects, as well as streamlined and more efficient airflow 705and heat exchanging.

FIGS. 8A and 8B illustrate in bottom plan views exemplary foot andscroll geometries for an integrated fan assembly according to variousembodiments of the present disclosure. FIG. 8A depicts a scroll geometry800 similar to that which is set forth above, with an impeller 281 beingdisposed within a fan assembly integrated within a foot 220. Foot 220can have various fan assembly inlets 285 and fan assembly outlets 286that are integrally formed as part of the foot 220. As shown, impeller281 can be concentrically located at the center of foot 220, such thatthe impeller is centered within all of the fan assembly inlets 285 andfan assembly outlets 286. As noted above with respect to FIG. 7, such aconcentric arrangement may result in a need for a scroll profile 226 ator near the location where airflow enters the impeller 281, such as tocreate a throat or otherwise create a desirable pressure build up alongthe length of scroll profile 226. Such a feature can be preferable forthe operation of an impeller and fan assembly in many instances.

Alternatively, FIG. 8B depicts a scroll geometry 801 that also includesan impeller 881 being disposed within a fan assembly integrated within afoot 220, which has various fan assembly inlets 285 and fan assemblyoutlets 286. Impeller 881 is located at an off-center position withinfoot 220, which can then result in an effective scroll profile at ornear the location where airflow enters the impeller 881 without havingto form such a scroll profile in the foot 220 or as another separatefeature. This then results, however, in a loss of concentric design forthe overall fan assembly, which may require design adjustments at otherlocations.

FIG. 9 illustrates a flowchart of an exemplary method of cooling anelectronic device according to various embodiments of the presentdisclosure. Method 900 can be carried out at least in part by anassociated processor or other controller that may be located on theelectronic device for which cooling is to be provided, for example.Method 900 starts at process step 902, where ambient air can be drawninto the electronic device through one or more inlet vents in thehousing. This can be done through vents in a housing foot, for example,such as that which is set forth above. At a following process step 904,the ambient air can be directed over a shroud and into an impeller.Again, this can be involve a shroud, impeller, and/or other relatedcomponents such as those set forth above.

At a process step 906, the impeller can be rotated to force the ambientair outward therefrom. Such an impeller rotation can be controlled by anassociated processor or other controller, such as one that might belocated on the subject computing or electronic device. Rotating theimpeller can also facilitate the performance of other process steps 902through 910, such as through the creation of a continuous airflow andthe contributions of component designs and arrangements, as will bereadily appreciated. At a subsequent process step 908, the ambient aircan be passed through a fin stack in order to exchange heat with one ormore other electronic device components. The heated air can then beforced out of the electronic device through one or more outlet vents inthe housing. Again, this can be done through vents in a housing foot,such as that which is set forth in greater detail above.

For the foregoing flowchart, it will be readily appreciated that notevery step provided is always necessary, and that further steps not setforth herein may also be included. For example, added steps that involvesensing when cooling is needed may be added. Also, steps that providemore detail with respect to the design or assembly of the electronicdevice in a particular conducive manner may also be added. Furthermore,the exact order of steps may be altered as desired, and some steps maybe performed simultaneously. In some embodiments, all of steps 902through 910 may be performed at the same time for different portions ofambient and then heated air.

FIG. 10 illustrates in block diagram format an exemplary computingdevice 1000 that can be used to implement the various components andtechniques described herein according to various embodiments of thepresent disclosure. In particular, the detailed view illustrates variouscomponents that can be included in the computing or electronic device100 illustrated in FIG. 1, among other possible computing or electronicdevices. As shown in FIG. 10, the computing device 1000 can include aprocessor 1002 that represents a microprocessor or controller forcontrolling the overall operation of computing device 1000. Thecomputing device 1000 can also include a user input device 1008 thatallows a user of the computing device to interact with the computingdevice 1000. For example, the user input device 1008 can take a varietyof forms, such as a button, keypad, dial, touch screen, audio inputinterface, visual/image capture input interface, input in the form ofsensor data, etc. Still further, the computing device 1000 can include adisplay 1010 (screen display) that can be controlled by the processor1002 to display information to the user (for example, a movie or otherAV or media content). A data bus 1016 can facilitate data transferbetween at least a storage device 1040, the processor 1002, and acontroller 1013. The controller 1013 can be used to interface with andcontrol different equipment through and equipment control bus 1014. Thecomputing device 1000 can also include a network/bus interface 1011 thatcouples to a data link 1012. In the case of a wireless connection, thenetwork/bus interface 1011 can include a wireless transceiver.

The computing device 1000 can also include a storage device 1040, whichcan comprise a single disk or a plurality of disks (e.g., hard drives),and can include a storage management module that manages one or morepartitions within the storage device 1040. In some embodiments, storagedevice 1040 can include flash memory, semiconductor (solid state) memoryor the like. The computing device 1000 can also include a Random AccessMemory (RAM) 1020 and a Read-Only Memory (ROM) 1022. The ROM 1022 canstore programs, utilities or processes to be executed in a non-volatilemanner. The RAM 1020 can provide volatile data storage, and storesinstructions related to the operation of computing device 1000.

The various aspects, embodiments, implementations or features of thedescribed embodiments can be used separately or in any combination. Theforegoing description, for purposes of explanation, used specificnomenclature to provide a thorough understanding of the describedembodiments. However, it will be apparent to one skilled in the art thatthe specific details are not required in order to practice the describedembodiments. Thus, the foregoing descriptions of specific embodimentsare presented for purposes of illustration and description. They are notintended to be exhaustive or to limit the described embodiments to theprecise forms disclosed. It will be apparent to one of ordinary skill inthe art that many modifications and variations are possible in view ofthe above teachings.

What is claimed is:
 1. An electronic device, comprising: a housing atleast partially defining an internal cavity with a shroud extending fromthe housing, wherein the housing defines a plurality of air ventsincluding a first subset of air vents and a second subset of air vents,wherein the shroud is formed extending from the housing radially inwardof the first subset of air vents, and wherein the shroud defines anaperture through the shroud to the internal cavity; a fan assemblydisposed within the internal cavity of the housing; and a fin stack atleast partially disposed about the fan assembly along the second subsetof air vents.
 2. The electronic device of claim 1, wherein the shrouddefines a flow path extending from the first subset of air vents of theplurality of air vents to the aperture defined through the shroud abouta central axis of the internal cavity.
 3. The electronic device of claim1, further comprising a seal extending about the second subset of airvents of the plurality of air vents and on which the fin stack isseated.
 4. The electronic device of claim 3, wherein fins of the finstack defines an arcuate shape.
 5. The electronic device of claim 1,further comprising a circuit board positioned across the shroud.
 6. Theelectronic device of claim 5, further comprising a heat pipe extendingfrom the fin stack at a first end, wherein a second end of the heat pipeextends across the aperture defined through the shroud.
 7. Theelectronic device of claim 6, wherein the second end of the heat pipe iscoupled with a heat stage configured to transfer heat from the circuitboard to the heat pipe.
 8. The electronic device of claim 7, wherein theheat stage is positioned between the heat pipe and the circuit board. 9.The electronic device of claim 7, further comprising an air cylinderextending between the heat pipe and the heat stage.
 10. The electronicdevice of claim 9, wherein the air cylinder comprises a sidewallextending about the plurality of air vents to at least partially definea volume within the electronic device.
 11. An electronic device,comprising: a housing including a shroud at least partially extendingfrom a base of the housing, wherein the housing defines a plurality ofair vents within the housing including a first subset of air vents and asecond subset of air vents, and wherein the shroud defines an aperturethrough the shroud accessing an internal volume within the housing; anda fin stack coupled with the shroud, wherein the internal volume isdefined by the shroud, and the fin stack, wherein the first subset ofair vents of the plurality of air vents are disposed external to theinternal volume, wherein the second subset of air vents of the pluralityof air vents are disposed within the internal volume, and wherein thefin stack extends across the second subset of air vents.
 12. Theelectronic device of claim 11, further comprising a circuit boardpositioned across the shroud.
 13. The electronic device of claim 12,further comprising a heat pipe extending from the fin stack across theaperture defined through the shroud.
 14. The electronic device of claim13, wherein a portion of the heat pipe extending across the aperturedefined through the shroud is coupled with a heat stage configured totransfer heat from the circuit board to the heat pipe.
 15. Theelectronic device of claim 11, further comprising a fan assemblydisposed within the internal volume.
 16. The electronic device of claim15, wherein the air vents extend uniformly about the fan assembly. 17.The electronic device of claim 11, wherein an airflow path is definedfrom the first subset of air vents, through the aperture through theshroud, and to the second subset of air vents.
 18. An electronic device,comprising: an upper housing; a lower housing coupled with the upperhousing, the lower housing including a shroud integrally formed with thelower housing, wherein the lower housing defines a plurality of airvents through the lower housing, and wherein the shroud partiallyencompasses an internal volume within the lower housing; a circuit boardpositioned within the electronic device and separating an internalvolume of the electronic device into an upper volume within the upperhousing and a lower volume including the internal volume within thelower housing; a fan assembly disposed within the internal volume of thelower housing; and a fin stack at least partially disposed about the fanassembly, wherein the fin stack at least partially defines the internalvolume in which the fan assembly is disposed.
 19. The electronic deviceof claim 18, further comprising a seal extending about a subset of airvents of the plurality of air vents and on which the fin stack isseated.
 20. The electronic device of claim 18, further comprising a heatpipe positioned within the lower volume and extending from the fin stackacross an access to the internal volume, wherein a portion of the heatpipe extending across the access is coupled with a heat stage configuredto transfer heat from the circuit board to the heat pipe.